• New Physics: Sae Mulli
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• v.68 no.11
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• pp.1208-1214
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• 2018

The one-step spin coating method is reported as an excellent thin film process because it can be easily used to fabricate high-quality methyl-ammonium lead tri-iodide ($MAPbI_3$) perovskite layers. One of the important things in the one-step spin coating method towards obtaining high-quality $MAPbI_3$ layers is the anti-solvent (AS) engineering, which consists of an one-step deposition of the $MAPbI_3$ film and dripping of the AS. The properties of the $MAPbI_3$ layer were found to be strongly influenced by the amount, dispensing speed, and spraying time of the AS solution. The $MAPbI_3$ solution was prepared by dissolving lead iodide and methyl-ammonium iodide in N,N-dimethylformamide and adding N,N-dimethyl sulfoxide. Diethyl ether (DE) was used for the AS solution. The results indicate that a $MAPbI_3$ layer appropriately sprayed with DE is beneficial for improving film quality and device efficiency because nucleation of $MAPbI_3$ layer is affected by the characteristics of DE, which affect the film's crystallinity, density, and surface morphology. The $MAPbI_3$ layer, which was optimized by using 0.7 mL of DE, a 3.03 mL/sec dispensing speed, and a 7 second time to spray after spinning showed the best efficiency of 13.74%, which was reproducible.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.1
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• pp.75-84
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• 2021

In this study, to evaluate deterioration propagation life and deterioration curve of the shop painted and field re-painted steel bridges, accelerated corrosion tests were carried out on 4 types of heavy-duty painting systems with different surface treatments. The surface treatments prior to painting were examined by hand tool(SSPC SP-2), power tool(SP-3,) or blast cleaning(SP-10) considering shop painting and field re-painting. The paint deterioration curves for each painting system and surface treatment were evaluated based on corrosion propagation from the initial paint defects. From the test results, the paint deterioration life of shop painted and field re-painted system was evaluated and compared by using corrosivity categories and durability performance evaluation of structural steel. The deterioration propagation life of shop and field paint was estimated in 18 to 21 years and 5.3 to 8.0 years with atmospheric corrosion category C4.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.6
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• pp.465-476
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• 2021

Scale and rust generation in water pipes is a common phenomenon when cast iron water pipes have been used for a long time. A physical water treatment device is known among various means for suppressing rust in a water pipe, and a zinc ionization device for putting zinc metal into a pipe and emitting the zinc cation into water is one of such devices. This research measured the amount of zinc ion generated, which is known to exhibit an effect of inhibiting rust and scale generation in a pipe, and examined the scale and rust inhibition effect of the ionization device installed for ground or building water supply. In the case of distilled water, the concentration of zinc ion increased by circulating water in the ionization device several times, and it was verified to be hundreds of ㎍/L, and in the case of discharging ground or tap water, it was verified to be tens of ㎍/L. In addition, a verification pipe was installed to confirm the change inside the pipe before and after installation of the zinc ionization device, and the internal condition of the pipe was observed 3 months to several years after installation. It was confirmed that the corrosion area of the surface of the pipe was no longer increased by installing a corrosion inhibitor, and if the pipe was already filled with corrosion products, the amount of corrosion products gradually decreased every year after installation. The phenomenon of fewer corrosion products could be interpreted as expanding the space in the pipe due to the corrosion product as Fe₂O₃ adhered to the inner surface of the pipe and turned into a smaller black Fe₃O₄. In addition, we found that scale such as CaCO₃ together in the corrosion by-products gradually decreased with the attachment of the ionization device.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.85-92
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• 2022

In order to identify the factors and problems in which military sexual violence is a continuous and repeated blind spot, this study conducted a content analysis focusing on articles of military sexual violence incidents covered in Internet news from January 2010 to June 15, 2021. carried out. As a result of the study, structurally unequal power relations, authoritarian and closed military organizational culture, internal military response system that is distrustful of passive responses to sexual violence, and enveloping family-friendly investigations and tolerant punishment of perpetrators are blind spots despite the Ministry of National Defense's efforts to improve. factors that exist. Underlying this, the compensatory spirit caused by the conscription system and the negative effects of the patriarchal system are embodied in the national sentiment, suggesting that the sense of crisis of division and an overly permissive attitude toward the military act as a factor that slows change. As an improvement plan according to the results, it is necessary to entail the establishment of a civilian-centered judicial institution, strong punishment of perpetrators, and limited pension payment, as well as honorable punishment such as 'class demotion' in the military culture with a clear hierarchical relationship. Taken together, we can see that most military sexual violence is caused by a hierarchy, and it strongly suggests that the main cause of sexual violence is unequal power relations.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.283-294
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• 2022

In this era of globalization, people's knowledge and cultural aesthetics are strongly influenced by the cultures of different countries, and diversified art forms have broken the traditional art framework, so how to stick to the essence of the country's traditional culture and make it inherited has became an important issue that cannot be ignored in the development of music today. Tan Dun, as one of the representative figures of Chinese contemporary music, has brought important inspirations to the development of Chinese music. With bold and free conceptions, innovative personality, unique Chinese tradition and international perspective. With a spirit of breaking down the barriers between tradition and modernity, East and West, and a concept of integrating multiple cultures into one, he has become a unique figure in the world of music. As researchers in composition, not only do we take on the responsibility of passing on Chinese culture, but we also need to explore the future development direction of Chinese music. Therefore, this paper takes Tan Dun's four traditional musical elements of organic music, Buddhist culture, witchcraft beliefs, folk songs and opera in his works and examines how Tan Dun perfectly blends traditional Chinese music culture with contemporary music language. And explore how the domestic traditional culture co-exists with modernity in today's diverse world.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.6
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• pp.787-792
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• 2022

In winter, the excessive use of deicing salt deteriorates concrete pavement durability. To reduce the amount of deicing salt used, phase-change materials (PCMs) potentially offer an alternative way to melt snow through their latent heat storage characteristics. In this research, thermal energy storage concrete was developed by using PCM-impregnated expanded clay as 50 % replacement to normal aggregate by volume. In addition, to improve the thermal efficiency of PCM lightweight aggregate (PCM-LWA)-incorporated concrete, multi-walled carbon nanotubes (MWCNTs) were incorporated in proportions of 0.10 %, 0.15 %, and 0.20 % by binder weight. Compressive strength testing and programmed thermal cycling were performed to evaluate the mechanical and thermal responses of the PCM-LWA concrete. Results showed a significant strength reduction of 54 % due to the PCM-LWA; however, the thermal performance of the PCM-LWA concrete was greatly improved with the addition of MWCNTs. Thermal test results showed that 0.10 % MWCNT-incorporated concrete had high thermal fatigue resistance as well as uniform heat flow, whereas specimens with 0.15 % and 0.20 % MWCNT content had a reduced thermal response due to supercooling when the ambient temperature was varied between -5℃ and 10℃.

• Analytical Science and Technology
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• v.19 no.5
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• pp.433-440
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• 2006

A HPLC/UV method was developed and validated for the rapid and simultaneous determination of urinary metabolites of organic solvents, mandelic acid, hippuric acid, phenylglyoxylic acid, ortho-, meta- and para-methylhippuric acid, using a monolithic column. The mobile phase was composed of tetrabutylammonium bromide as ion-pairing reagent with a flow rate of 2.4 mL/min. The total run time was less than 2.5 min for all six analytes. Good linearities were obtained for all the metabolites with correlation coefficients above 0.9993. Intra-day precision, accuracy and inter-day precision was 0.01~7.32%, 83.9~116.3% and 0.01~7.16%, respectively. The method was validated and confirmed by quantification of the quality assurance samples of Industrial Safety and Health Research Institute, Korea Occupational Safety and Health Agency.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.41-41
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• 2020

가지(Solanum melongena L..)는 가지과 식물로 인도 동부가 원산지로 추정이 되며 우리나라를 포함해서 전세계적으로 널리 이용되고 있다. 가지는 다른 과채에 비해 비타민 함량은 낮으나 무기질과 폴리페놀, 식이섬유가 풍부하고 항균, 항암, 항산화활성을 가지는 것으로 보고되어 있다. 본 연구에서는 국내외에서 수집된 가지 유전자원의 형태적 특성을 조사하여 품종 육성을 위한 기초자료를 제공하고자 하였다. 본 연구에 사용된 가지 자원은 필리핀 78자원, 영국 78자원, 중국 45자원, 한국 12자원 등 16개 국가에서 수집된 459자원을 대상으로 하였다. 가지 유전자원의 생육 특성은 반직립형 437자원으로 가장 많았으며 직립형 15자원, 수평형 7자원으로 조사되었다. 하배축의 안토시아닌은 301자원이 있는 것으로 조사되었고 줄기 안토시아닌 축적은 258자원에서 조사되었다. 가시의 여부는 줄기에 31자원, 잎에 30자원이 조사되었으며 IT189682는 특이적으로 줄기에서만 가시가 조사되었다. 화색의 경우 흰색 31자원, 자주 207자원, 연자주 217자원, 흰자주 4자원으로 조사되었으며 꽃의 크기는 중간이 340자원으로 대부분을 차지했으며 큰 꽃 28자원, 작은 꽃 1자원(IT136568)으로 조사되었다. 과실의 형태는 원형 77자원, 타원형 27자원, 난형 31자원, 서양배형 57자원 곤봉형 88자원, 원통형 84자원, 긴원통형 95자원으로 다양하게 조사되었으며 과실 성숙색은 녹색 94자원, 흰색 16자원, 녹자주 67자원, 백자주 21자원, 자주 240자원, 주황 8자원, 노랑 13자원으로 조사되었다. 과실의 길이는 1.4(IT283605) ~ 40.5cm(K003875)로 평균 17.4cm였으며 두께는 0.7(IT283605) ~ 13.7cm(K162043)으로 평균 5.6cm 조사되었다. 본 실험에서 조사된 가지유전자원의 형태적 특성은 가지 선발에 있어 기초 정보로 활용 가능할 것이며 추가적으로 농업형질, 기능성 물질 분석등의 가지 육종 프로그램을 위한 다양한 평가 및 선발이 필요할 것이다.

• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.26-30
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• 2003

Cytochrome P450 (CYP) induction was determined in microsomes of three aquacultured fish species (Sebastes schlegeli, Paralichthys olivaceus and Pagrus major) and two wild fish species (Mugil cephalus and Stephanolepis cirrhifey) in vitro exposed to $\beta$-naphthoflavone (BNF). The microsomes of five fish were exposed to BNF (5 mM or 10 mM) in dimethylsulfoxide at $30^{\circ}C$ for 9 hr. The CYP contents in most fish increased according to exposure duration for 3 or 5 hour, and then decreased, while steady increase of CYP was observed in P. major for 9 hour. The induction of CYP contents in aquacultured fish species (207~422%) were higher than those in wild fish species (206~207%).

• Economic and Environmental Geology
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• v.57 no.3
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• pp.343-352
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• 2024

Composition analysis and lead isotope ratio analysis were conducted to determine the coloring machanism on lead glaze used in Gyeongbokgung Palace and the provenance of the lead used as a flux. 31 blue tiles were classified into green, blue, and yellow. The chemical analysis of lead glazes on the blue tiles revealed that Pb, Si, and Cu were the main components, and trace amounts of Fe, Ca, Mg, and Al were detected. The Cu content was high in blue lead glaze, while Cu was not detected in yellow or brown lead glaze which instead had high Fe content. Therefore, it was found that lead was used as a flux and copper oxide as a coloring agent in the production of lead glaze. In addition, the lead isotope ratios of the lead glaze used in the blue tiles of Gyeongbokgung palace were plotted in zone 3 on the distribution map of lead isotope ratios on the Korean Peninsula, which includes Chungcheong-do and Jeolla-do. It is presumed that the flux for the lead glaze was sourced from galena found in these regions. The lead isotope ratios of the green glaze from the Three Kingdoms and Unified Silla period were mostly located outside the Korean Peninsula, showing that the provenance of lead had changed. In particular, the lead isotope ratios of the green glaze from the Three Kingdoms and Unified Silla period suggest exchange with neighboring countries. Also the lead isotope ratios of the green glazes from the same temple are different, so it is believed that they were made at different times or in different workshops.